Extinct meteorite changes our understanding of the solar system
No one knows what the flow of meteorites to Earth has been like over the last 500 million years, or before that. Researchers have simply assumed that the composition of the meteorites was the same back then as it is now and that the flow of meteorites remained the same over time. But this is probably not the case, according to Birger Schmitz who made the discovery at a quarry by Kinnekulle outside Lidköping, together with Mario Tassinari, honorary doctor at Lund University.
The discovered fossil turns our current understanding of meteorites upside down, because the type is not represented among present-day meteorites. It has a different composition than all known groups of meteorites.
“This gives us a strong indication that, contrary to current perception, the difference between the meteorite flow to Earth 470 million years ago and now may be as great as when comparing wildlife back then to animals of today”, says Birger Schmitz.
He and Mario Tassinari therefore call it an “extinct meteorite” – a sort of meteorite dinosaur. By extinct they mean a meteorite whose parent body was destroyed in ancient times, and which will therefore never again fall on Earth.
The finding indicates that today’s meteorites do not fully represent what is in the asteroid belt. According to Birger Schmitz, different processes in space could affect from which parts of the asteroid belt the meteorites come during different geological periods.
“The extinct meteorite that we discovered will profoundly change the perception of what meteorites are. Our understanding of the history of our solar system is perhaps largely based on a highly fragmentary sample of the material that is actually out there. If so, it will have major consequences”, says Birger Schmitz.